NOTES: Expenditure refers to the value of work done on construction projects underway during a given period time, regardless of when work on each individual project was started or when payment was made to the contractors.

Public expenditures on transportation construction is a measurement of growth of system capacity. Construction includes new buildings, infrastructure, renovations, site preparation, and other materials and structures involved in construction. Maintenance of existing facilities and structures is not included.

Construction expenditures on completely new routes and terminals are direct additions to system capacity. Construction expenditures (including renovations, expansions, conversions, etc.) on existing transportation infrastructure may improve maintenance and system management, safety, and other attributes that increase capacity.